Steam treatment of fabrics

ABSTRACT

A process and apparatus for treating textile material in which the textile material is subjected to a continuous compressive load characterised in that at at least one location this compressive load is increased. It is preferred that the textile material be subjected to this treatment in an atmosphere of saturated steam at a temperature greater than 100*C.

" United States Patent Bissitt Sept. 16, 1975 [54] STEAM TREATMENT OFFABRICS 2,899,264 8/1959 Griffiths et a1 .568/5 D X 3,046,771 7 1962Bail 68 5 E [75] Invent: Smckwe Bissitt Bradford 3 357 111 1211967Fieiszler et a1..... 34/ 115 England 3,440,736 4/1969 Fleissner et a168/D1G. 5 [73] Assignee: Wire and Mather & Platt, Ltd., 322:2: gMancheser England 3,563,065 2 1971 Fleissner... 68/DIG. 5 22 Filed; S 201972 3,595,035 7/1971 Stringer 68/5 D [211 App]' 290669 Primary ExaminerEdward L. Roberts Assistant ExaminerPhilip R. Coe [30] ForeignApplication Priority Data Attorney, Agent, or Firm--Sughrue, Rothwell,Mion,

Sept. 22, 1971 United Kingdom 44119 71 Zirm & Macpeak [52] US. Cl.8/l49.3; 26/51.4; 68/5 D [57] ABSTRACT [51] Int. Cl. D0613 3/18 Field ofSearch H 49.3 6 5 A rocess and apparatus for treating textile materialin 68/158 DIG 5 44 99 34/155 162 l 144 18 which the textile material issub ected to a contmuous compressive load characterised in that at atleast one location this compressive, load is increased. It is pre- [56]References Cited ferred that the textile material be subjected to thisUNITED STATES PATENTS treatment in an atmosphere of saturated steam at a1,315,698 9/1919 Bailey 68/44 X temperature greater than 100C. 2,431,37211/1947 Cook et al. 68/5 D X 2,724,254 11/1955 Zanger 68/158 x 5 091m, 5Drawing Figures PATENTEH sE 1 I915 SHEET 2 [IF 2 STEAM TREATNIENT OFFABRICS This invention relates to a method of and apparatus for thecontinuous treatment of textile materials to effect a permanentcompression efiect thereon. It is preto the surface of the fabric in adirection having a com-' ponent normal to the surface, and includes theeffect known as lustre.

While any textile material may be treated by the method and apparatus ofthe present invention, the treatment is especially advantageous whenapplied to textile fabrics containing a substantial proportion ofkeratin fibre.

It is known that'if a textile fabric containing a substantial proportionof keratin fibre, such as wool, is subjected to compression in saturatedsteam at a temperature above 100C the fabric will retain its compressedform for a long durationwhen removed from that environment, despitesubsequent treatments in the presence of moisture at temperatures up to100C. This effect is commonly known as permanent set.

On the other hand, compression effects imparted in the presence ofmoisture at temperatures below 100C may be removed by a subsequent wettreatment at 100C. This is known as temporary set.

It is an object of the invention to impart to a fabric a durablecompressive effect while imparting at most a low degree of compressiveeffect that is of a temporary nature.

The invention procedes from a realization that whereas a light load willeffect only a small compression of a fabric, a heavy load is applied toa fabric for a short period, the total recovery of the fabric from itslarge compression on removal of the heavy load can be prevented by theimposition of the same light load, and the final compression under thelight load is then greater than the compression resulting from the lightload alone. While this is true in normal conditions, i.e. conditions atatmospheric pressure, it is particularly pronounced in a saturated steamatmosphere at a temperature greater than 100C.

According to the present invention there is provided a method ofimparting a durable compression effect to textile material, comprisingthe steps of moving the textile material into and out of a treatmentzone, maintaina ing the material under a substantiallycontinuouscompresssive load during its movement along a predetermined path withinsaid zone, and increasing the load at at least one location along saidpath.

Preferably, the treatment zone is a steaming zone maintained at atemperature greater than 100C. The steaming zone preferably containssaturated steam.

Preferably, the material is removed from the steaming zone with anapplied load less than the continuous compressive load.

Also according tothe present invention there is provided apparatus foruse in impartinga durable compression effect totextile material,comprising a vessel for providing a treatment zone for the textilematerial, means for constraining the material to follow a predeterminedpath through said zone,means for applying a substantially'continuouscompressive load to the material as it is moved along said path, andmeans for further increasing the compressive load at at least onelocation along said path.

Preferably, the constraining means is a pair of endless belts betweenwhich the fabric is sandwiched, the fabtic/belt sandwich beingconstrained to follow a curved path.

Preferably also, the compressive load applying means comprises means fortensioning the belts and rollers around which the tensioned belts aremoved in a curved path.

The means for further increasing the compressive load is preferably oneor more pressure nips.

Embodiments of the present invention will now be described, by way ofexample, with reference to the accompanying drawings, in which:

FIG. 1 is a diagrammatic elevation of a preferred form of apparatus;

FIG. 2 is an alternative form of the apparatus;

FIG. 3 shows an alternative roller detail of the apparatus of FIG. 2;

FIG. 4 illustrates diagrammatically the tension in a belt or blanketpassing over a curved surface; and,

FIG. 5 illustrates graphically the result on material thickness ofapplying and removing a series of compressive loads.

Referring to FIG. 1, the apparatus comprises a pressure vessel orautoclave 10 provided with fluid inlet and outlet means. Within thisvessel 10 there is disposed three pressure rollers 11 spacedequiangularly around a nip roller 12 lying along the vessel axis. Amotor 13 external of the vessel 10 drives a gearwheel l4 coaxial "withthe nip roller 12. The gearwheel 14 is not drivingly fast with the niproller 12 which is freely rotatable. The gearwheel 14 meshes with agearwheel 15 fast with the shaft 16 of each pressure roller 11 so thatthese pressure rollers 11 are driven from a common source, i.e. themotor 13 and gearwheel 14.

These gearwheels l4 and 15 are internal of the pressure'ves sel 10, theroller shaft 16 of gearwheel 14 passing through appropriate seals in thevessel wall as will be manifest to anyone skilled in the art.

At each end, each pressure roller shaft 16 is carried in a block 17 onwhich acts a pressure-applying device which, in this instance, is adiaphragm unit 18 such that application of air pressure to one side ofthe diaphragm 19 causes a pressure to be applied to the blocks 17 via,for example, a rod 20 and consequently to the pressure rollers l 1 thusincreasing the pressure at their nips with the nip roller 12. Suchdiaphragm units are well known to those skilled in the art and will notbe described further. It will be manifest that other convenientpressureapplying means may alternatively be employed.

These diaphragms units 18 are internal of the pressure vessel 10.

The pressure vessel 10 has a top inlet and outlet extending along asubstantial part of its length and appropriate seals 21 are disposed atthe inlet and outlet so as to allow passage of material therethroughwithout loss of pressure from the vessel 10. A convenient form of seal21 is disclosed in British Pat. No. 1,001,508 in the name of Mather andPlatt Limited.

A freely rotatable guide roller 22 is disposed between adjacent nips,and a freely rotatable guide roller 23 is disposed adjacent the vesselinlet and the vessel outlet.

A conveying arrangement is provided for carrying, for example, fabric inopen width through this vessel l0. This arrangement consists of twoendless belts or blankets formed of any convenient material which willwithstand the treatment conditions within the'vessel 110 withoutinterfering with the treatment of the fabr'ic..rAn example of such amaterial is a high temperature nylon. Thetwo belts form a sandwich withthe fabric as the central layer.

The inner endless belt 24 passes around (from the top left hand comer ofFIG. 1) a tension control roller 25, a double swivel roller guide unit26, a take-up roller 27, guide rollers 28 and 29, a first curved plate30, a guide roller 31, a second curved plate 32, into the pressurevessel where it follows a path between the guide roller 23 and toppressure roller 11 around guide roller 22 and then between the latterand the right-hand pressure roller 11, between the three nipsconstituted by the pressure rollers 11 and nip roller 12, between theleft-hand pressure roller and its guide roller 22, around the latter,between the top pressure roller 11, and guide roller 23 and then out ofthe pressure vessel 10, along a third curved plate 33, over a guideroller 34 and back to the tension control roller 25;, Y

The various rollers and plates external of the .vessel 10 areeitherconveniently supported on the frame of the apparatus or associatedframework or are mounted indirectly on the vessel 10.

The. tension-control roller 25 and take-up roller 27 are movably mountedon the frame 35 so that they can be adjusted by any convenient meansknown in the art for belt tensioning and take-up purposes. -The plates30, 32 and 33 are preferably formed of I stainless steel.

' The outer endless belt 36 passes around a pair of pull rollers 37, 38,a tension control roller 39, a take-up roller 40, a guide roller 41,another take-up roller 42,-a

' guide roller 43, under the pressure vessel 10, around a mounted on themachine frame 35 which is slotted at 47 and 48 m allow removal of therollers 38 and 41 respectively during fitting of the belt 36 orindirectly on the vessel 10, the roller 39 being freely supported in aloop of the belt.

The take-up rollers 40, 42 are adjustably mounted for take-up purposes.

The path of the fabric F is from a supply (not shown) over a guideroller 49, through swivel tension tubes 50,

through a conventional weft-straightening device 51, over arubber-covered fabric pull roll 52, under a compensator roll 53 and thenit follows the path of the outer belt from roller 46, it beingsandwiched between the belts at roller 29. At roller 34 the fabric Fisled away in any desired direction. The compensator roll 53"automatically operates a control 53A of a DC geared motor (not shown)which drives the fabric pull roll 52.

The abovedescribed apparatus can be used to effect "a permanent lustreor other compression effect on a C-Etextile fabric with saturated steamat a temperature greater than 100C.

I The fabric to be treated may be one containing a substantialproportion of keratin fibre suchas wool.

FIG. 4 illustrates diagrammatically that the tension in a belt passingover a curved surface exerts a radial press Reference is now made to atensioning roller 69.

sure on the surfa'ceandthus 'on any material between itself and saidsurface. v I

. Since,iri the abovedescribed apparatus, the fabric is carried, as.aforesaid, th rough the pressure vessel 10 by the belts 24 and 36 anddue to the fact that the belts are; tensioned andjfollow a non-linearpath internally of the vessel 10, a substantially continuous compressiveforce is applied to the fabric by the beltsl'This compressive-forceisincreased at the nips within the pressure vessel 10. 1 i

FIG. 5 indicates graphically the result on fabric thickness of applyingand removing a series of compressive loads in an environment ofsaturated steam at a temperature greater than 100C.

At time intervaLAB a small load s isapplied resulting in a fabricthickness, originally t, reducing to t,. On removal of the load at B,the thickness t is gradually recovered. Application of a great load g atC reduces the thickness to t, where, of course, vt,, t,. Again, onremoval of the load the fabric reverts gradually to its originalthickness r. If a combined load s gis applied as at D the resultantthickness t, t However, the important observation is that on removal ofload g but retainingi load s as at point E, the thickness recoveryproceeds only as far as t, where t t,. If the heavy load is appliedbriefly a second time (point F) and removed (point G) there is stillgreater residual compression 1 i.e. z z r,. t g v I, Thus, in thepresent invention a continuous small or light load exerted by the beltsis supplemented at one or more locations (nips 11, 12) by a greaterload, and the resultant compression achieved is intermediate that causedby the small or light load and the greater load. Since the compressiontakes place in an environment of saturated steam at a temperaturegreater than 100C the compressive effect after removal from the pressurevessel 10 is durable.. I I

When the fabric F leaves the vicinity of the curved .plate 33 and guideroller 34 the belts 24 and 36 separate andthe fabric is no longersubjected to a compressive force. V A g the modified apparatus of FIG.2, which has a pressure vessel or autoclave with an inlet 61 and outlet62having seals as aforesaid'a'n d through which a fabric 63 in openpasses sandwiched between endless belts 64 and 65. Externally of thevessel 60, the belt 64 passes over idler rollers' 66 and a displaceabletensioning roller 67. I l

The belt similarly passes over idler rollers 68 and In the vessel 60,the fabric/belt sandwiched is guided in a curved path (shown, forclarity, in dotted lines) defined by guide rollers 70 to 73, a rotatablehollow cylinder 74 and fixed curved plates 75. Guide roller 70 is ofsmall diameter so that the distance of the fabric/belt sandwiched fromits last contact with roller 70 to the outlet 62 is small. The cylinder74 preferably driven by any convenient 'means so as to move the belts64'and 65 and the fabric 63 sandwiched between them in the directionindicatedby'the" arrows."

.Pressurerollers 76 are arranged aroundthat portion of the cylinder 74,covered by the fabric/belt sandwich and are urged against: the cylinderby conventional means '(not shown) 1 Outside the vessel'60 the fabric isfed to the inner belt 65 over a roller 77'and 'aft'er'withdrawal is led'away from the belts by a roller 78. f t I In FIG. 3, there is shown analternative to the pressure rollers 76, namely a curved plate 79 urgedby a fluid pressure cylinder 80 against the cylinder 74.

This apparatus operates in the same way as the apparatus of FIG. 1.

On leaving the guide roller 70, the path of the belts is substantiallystraight and the only substantial compressive force exerted on thefabric 63 is that caused by its passage through the outlet 62 which may,as aforesaid, be a conventional pressure seal. Outside the vessel 60,where the temperature falls to below 100C, thecompressive force whichleads, under these conditions, to a temporary effect is thus reduced toa minimum.

Modifications are possible without departing from the scope of theinvention as claimed. Thus, the curve surfaces defining the path of thefabric may be composed solely of rotatable rollers or of fixed plates orof both rollers and plates in other configurations or combinations. Thepressure rollers may be replaced by pressure plates which may be convexor concave or linear with respect to the cloth/belts sandwich.

The degree of compression exerted can be varied by varying thetemperature in the vessel, the tension of the belts, the number andpressure of the pressure rollers or the like, the speed of movement ofthe fabric or pressure of the seals, and the invention includescontrolling these parameters.

In using the apparatus of FIG. 1 to carry out the method of the presentinvention, ie the application of permanent compressive effects to fabricit will be manifest that the weft straightener 51 may not be requiredand can therefore be bypassed by the fabric.

The conditions within the pressure vessel can be adapted to suitrequirements. For example, a treatment may require the use ofsuperheated steam, vacuum conditions, or pressure above and belowatmospheric pressure. In other words, the apparatus can be used in anyapplication where it is advantageous to compress the fabric.

What is claimed is:

1. Apparatus for use in imparting a durable compression effect totextile material, comprising: (a) a pressurized vessel for providing atreatment zone for the textile material, (b) a pair of endless tensionedbelts between which the textile material is sandwiched for applying asubstantially continuous compressive load to the textile material andfor constraining the textile material to follow a curved path throughsaid pressurized vessel, (c) means for tensioning the endless belts, (d)a single nip roller centrally located within said pressurized vessel,and (c) three pressure rollers equidistantly spaced about and adjacentto the periphery of said nip roller having their rotating axes parallelto said single nip roller within said pressurized vessel to increase thecompressive load on said textile material as it passes between said niproller and said pressure rollers.

2. A method of imparting a durable compression effect to textilematerial comprising the steps of:

a. placing said textile material between a pair of endless tensionedbelts,

b. moving the pair of belts and the textile material along a curved pathwithin a pressurized vessel, to exert a substantially continuouscompressive load on the textile material,

c. increasing the compressive load at at least one location along saidpath, by passing said textile material between at least one nip rollerand at least one pressure roller located within said pressurized vessel,and

d. steaming the textile material at a temperature greater than C duringat least a portion of its travel through the pressurized vessel.

3. The method of claim 2, wherein the step of steaming the textilematerial is accomplished by using saturated steam at a temperaturegreater than 100C.

4. The method of claim 2 in which the textile material is a fabriccontaining a substantial proportion of keratin fiber.

5. The method of claim 2, in which the material is a synthetic orblended textile.

1. Apparatus for use in imparting a durable compression effect totextile material, comprising: (a) a pressurized vessel for providing atreatment zone for the textile material, (b) a pair of endless tensionedbelts between which the textile material is sandwiched for applying asubstantially continuous compressive load to the textile material andfor constraining the textile material to follow a curved path throughsaid pressurized vessel, (c) means for tensioning the endless belts, (d)a single nip roller centrally located within said pressurized vessel,and (e) three pressure rollers equidistantly spaced about and adjacentto the periphery of said nip roller having their rotating axes parallelto said single nip roller within said pressurized vessel to increase thecompressive load on said textile material as it passes between said niproller and said pressure rollers.
 2. A METHOD OF IMPARTING A DURABLECOMPRESSION EFFECT TO TEXTILE MATERIAL COMPRISING THE STEPS OF: A.PLACING SAID TEXTILE MATERIAL BETWEEN A PAIR OF ENDLESS TENSIONED BELTS,B. MOVING THE PAIR OF BELTS AND THE TEXTILE MATERIAL ALONG A CURVED PATHWITHIN A PRESSURIZED VESSEL, TO EXERT A SUBSTANTIALLY CONTINOUSCOMPRESSIVE LOAD ON THE TEXTILE MATERIAL, C. INCREASING THE COMPRESSIVELOAD AT AT LEAST ONE LOCATION ALONG SAID PATH, BY PASSING SAID TEXTILEMATERIAL BETWEEN AT LEAST ONE NIP ROLLER AND AT LEAST ONE PRESSUREROLLER LOCATED WITHIN SAID PRESSURIZED VESSEL, AND
 3. The method ofclaim 2, wherein the step of steaming the textile material isaccomplished by using saturated steam at a temperature greater than100*C.
 4. The method of claim 2 in which the textile material is afabric containing a substantial proportion of keratin fiber.
 5. Themethod of claim 2, in which the material is a synthetic or blendedtextile.